Spreader stoker apparatus



March 25, 1947.V D. J. MossHART 2,418,042

SPREADER sToKER APPARATUS Filed De. 22, 1944 2 Sheets-Sheet 1 wlTNEssEs: Y IVENTOR HLIJ DONALD JMQSSHART- March 25, 1947. D. J. MossHART 2,418,042

` SIREADER STOKER APPARATUS Filed Dee. 22, 1944 2 sheets-sheet 2 INVENTOR DONALD J. Mos SHART` ATTORNEY Patented Mar. 25, 1947 SPREADER STOKER APPARATUS Donald J. Yllloss-hart, Ardmore, Pa., assignor to Westinghouse Electric Corporation, East Pittsbluish, Pa., a .corporation of Pennsylvania Application December 22, 1944, Serial No. '569,346

2 Claims. i

This invention relates to stokers, Amore particularly to those of the fspreader or sprinkler type, and has for 1an object 'to provide improved @Online means therefor.

In stokers of this character, itis common vpractice to project fuel rearwardly through an opening in the furnace front wall to the grate :surface within the furnace, the opening in the furnace front wall generally being disposed a material distan-ce above the level of the grate surface.

In such constructions7 it has been found desirable .to provide means for cooling Vthe lower lip or edge of the furnace front wall opening, to protect the same from the intense ,heat encountered at this point in appara-tus of this character, particularly where much of the fuel `is burned in suspension and thus in close proximity to said lip.

Therefore, it is .a further object of the invention to provide means for conducting a cooling medium to the vicinity of the lower edge of the inlet feed opening ,in a furnace front wall.

Yet another objeci-l of the invention is to prol vide an adjustable air discharge nozzle arrangement adjacent the lower `edge Aof the fuel feed opening of a furnace wall.

Another object of the invention is to provide, in a furnace to which fuel is fed through an opening in a wall thereof by a feed device of the sprinkler or spreader type, means providing a transversely-extending series of air discharge nozzles for discharging a sheet or curtain of air rearwardly into the furnace combustion chamber, together with means whereby the angle of discharge of the air from the nozzles may be varied from externally of the furnace and during normal operation thereof.

These and other objects are effected by the invention as will be apparent from the following description and claims taken in connection with the accompanying drawings, forming a part of this application, in which:

Fig. 1 is a vertical sectional view through the front wall of a furnace incorporating the principles of the present invention;

Fig. 2 is a, fragmentary elevational view of the furnace front wall viewed from interiorly of the furnace along the line II-II of Fig. 1, looking in the direction indicated by the arrows, the heatresisting coating shown in Fig. 1 being omitted for the sake of clearness; and,

Fig. 3 is a fragmentary sectional view taken along the line III-III of Fig. 1, looking in the direction indicated by the arrows.

the reference character I3 indicates, in its entirety, the `fuel-feeding device of the sprinkler or spreader type, adapted to project fuel rearwardly through an opening l! in the front wall l2 `of the furnace i3, for combustion on the grates it and in the atmosphere thereabove.

More particularly,V the fuel-feeding mechanism comprises `a rotor it carried by a transverselyextending shaft i'iV and having mounted thereon a plurality of radially-extending fuel-impelling blades it and i9, adapted to engage fuel discharged frorn the rear edge of the spill plate Z0 by the transversely reciprocable feed `plate 2t. Fue-l `may be 4fed to the rear discharge edge of the spill plate 2l) by any suitable means (not shown).

The rotor t5 is housed by a partially cylindrical casing comprising the arcuate sections 23 and 24, both carried by the bracket 25, which bolted or otherwise secured to a vertical plate structure comprising the `lower plate 25 and the upper plate 2l, both secured to the outer face of the furnace front wall I 2. The upper plate 2l is provided with an opening .28 therein adapted to substantially overlie, and to be aligned with, the opening Il in the furnace front wall l2.

A casing 3i), of cast or fabricated construction, is secured to the rear side of the vertical plate 21 and forms therewith a chamber 3i, to which air under pressure is supplied by the conduit 32 (Fig. 2), flow of air through this conduit being controlled from externally` of the furnace by the damper 33.

Referring now to Figs. 2 and 3, it will be observed that, for ease in manufacture and assembly, the casing 3!) is made in a plurality of sections indicated 3Ga, 30h and 30o provided with rearwardly-extending vertical flanges 34 at the side edges, adjacent flanges being secured together by suitable means, such as the bolts 35. Y

Above the casing 30 and adjacent the lower edge of the fuel-feed opening 28 in the vertical plate 21, there is positioned a nozzle clamping structure comprising spaced members 36 and 3'! having opposed arcuate Surfaces between which is retained a nozzle manifold 38 of cylindrical cross section and preferably extending for the full width of the fuel-feed opening. The cylindrical manifold 38 is provided with a plurality of nozzle openings 39 preferably in the form of elongated slots (Fig. 2) adapted to discharge a sheet or blanket of air supplied to the interior of the manifold through the inlet opening im at the lower portion thereof. The chamber 3l is provided at its top with a discharge opening lll,V

whereby air supplied to the chamber by the duct 32 may pass upwardly through the opening 4| to the interior of the nozzle manifold 38, for discharge therefrom through the nozzles 39. Inasmuch as the air is supplied by conduit 32 to the chamber 3| throughout the entire height of the latter, it will be apparent that the entire plate structure and its associated parts will be cooled and protected by the air passing through `the chamber 3| to the nozzle manifold.

Inasmuch as it may be desirable to vary the angle of discharge of air from the nozzles 39 in accordance with changes in the character of the fuel being fed, the manifold 38 is' provided at one end with an extension 43, projecting through a side wall of the furnace and carrying suitable means by which it may be rotated about its horizontal axis, for example, the meshed gears 44 and 45 and the crank 46.

The rear vertical surface of the casing 30 is provided with a layer or coating of heat-resistant material 50, for example, cement, to portect the casing from the intense heat of the re within the combustion chamber. In order to securely retain the coating 50 in place on the vertical surface of the casing 30, the latter is provided with a plurality of ribs projecting rearwardly therefrom and preferably increasing in cross-sectional area in a rearward direction in order to provide, in eiect, a dovetailed connection with the heatresisting coating 50. v

While the rearward wall of the casing l30 may be inclined rather than Vertical, the latter construction has been illustrated in thedrawings and there is associated therewith a block or plate 53 of heat-resisting material, providing a, ledge 54 between the casing 30 and the forwardmost grate bar I4. To prevent accumulations of ne fuel upon this ledge 54, the air chamber 3| within the casing 30 is provided with a transversely-extending series of nozzle openings 55 adapted-to direct rearwardly a stream of air to sweep the ledge 54 and to project any fuel settling thereon rearwardly onto the lire bed onto the grates I4.

Preferably, although not necessarily, the Vertical plate 27 and the casing 30 are provided with a plurality of observation openings 69 extending therethrough and closed by covers or doors 6| at the exterior front of the furnace. As indicated in Fig. 1, these openings 50 extend through the air chambers 3|, but do not materially obstruct Vertical passage of air therethrough from the bottom to the top of the chamber.

tivelyassociated with the rear side of said plate While the invention has been shown in but one form, it will be obvious to those skilled in the art that it is not so limited, but is susceptible of various changes and modifications without departing from the spirit thereof.

What is claimed is:

1. In a Stoker, upright plate structure adapted to be` attached to a furnace wall and having an opening therein through which fuel may be impelled into the furnace, casing structure operastructure and providing a chamber below the opening, means for admitting air under pressure to said chamber, .and means near the top of the chamber for discharging air rearwardly from the chamber into the furnace, said means being ad- `justable from externally of the furnace to vary the angle of discharge of said air relative to the horizontal.

2. In a stoker; upright plate structure adapted for attachment to a furnace wall and having an opening therethrough for passage of fuel to the furnace; casing structure operatively associated with the rear side of the plate structure and providing a chamber extending downwardly from adjacent the lower edge of the opening; means for admitting air under pressure to said chamber; a horizontally-disposed nozzle manifold posi-r tioned just below and rearwardly of the lower edge of the opening, said manifold having a plurality of nozzle openings and being adapted to receive air from the chamber and to discharge the same rearwardly into the furnace through said nozzle openings; and mechanism operable from externally of the furnace for oscillating said nozzle manifold about its horizontal longitudinal axis, whereby the angle of discharge of air from the nozzle openings may be varied.

DONALD J. MOSSHART.

REFERENCES CITED The following references are of record in the 'lle of this patent:

UNITED STATES PATENTS Number Name Date 1,734,669 Frisch Nov. 5, 1929 1,994,445 Hardgrove Mar. 12, 1935 2,065 552 Beers Dec. 29, 1936 2,065,555 Beers Dec. 29, 1936 2,100,252 Hoiman Nov. 23, 1937 2,255,841 Bower Sept. 16, 1941 

